Most binaries (except for GTK+) live in /usr/local and are static PIC builds (i.e. they can be used in R packages without the need for runtime dylibs).

For more libraries, see the CRAN devpack. Sources for most of the above are available at the project sites or here.

Note (2009/01/15): ggobi binary was modified at the request of the authors to install in /usr/local/ggobi instead of the default /usr/local. CRAN binaries will reflect the change as well. Consequently, you will have to add /usr/local/ggobi/bin to your PATH and if you develop against ggobi /usr/local/ggobi/lib/pkgconfig to your PKG_CONFIG_PATH in order to see ggobi.